After the Young Vic got everybody talking with its casting of Michael Sheen in the title role of Hamlet, and more recently Sir Patrick Stewart in Bingo, the Hampstead Theatre has decided, too, that it is time to play the West End at its own game and get some big star names up on its hoardings.

Ben Chaplin, Tara Fitzgerald and Jemma Redgrave – with the great Roger Michell (Notting Hill) directing – make its production of Farewell to the Theatre all but unignorable. It has been fashionable to speak disparagingly of this plucky little establishment in recent years – its old boss Anthony Clark managed to make enemies out of certain unforgiving critics – but there is plainly a new feeling of confidence in Swiss Cottage now that his successor Edward Hall has got into his stride.

Richard Nelson’s work is, appropriately, about a man who, while a somewhat recondite subject these days, was a transforming influence in the theatre. Born in 1877, Harley Granville-Barker rejected the mannered and starchy Victorian approach to the business of staging drama, with its imperious managers, and helped to shift power away from them and to the directors, playwrights and actors.

He ran the Royal Court, encouraged more women to get into the business, and was among the first to speak of the need for a national, subsidised theatre.

Sir Peter Hall said that he had about him a “cool arrogance”, and this makes Chaplin – blessed with the same mane of lustrous dark hair that he had, together with somewhat dangerous eyes – perfect for the role. In the opening scene, he cuts an affectingly desolate figure, sitting on a bench in a park, bemoaning the fact that most modern theatre is all too often “rubbish” (plus ça change).

The year is 1916 and Granville-Barker is holed up in Williamstown, Massachusetts, in the midst of a divorce and with his best work (plays like The Voysey Inheritance and The Madras House) behind him.

He is lecturing at a local college and has fallen in with a set of arty British ex-pats who, while drawn to him, are also, to varying degrees, intimidated as they set about staging A Midsummer Night’s Dream. As his companions, Redgrave and Fitzgerald are on fine form, but it is Chaplin – intense, moody and radiating despair – who dominates.

Michell directs with his customary flair and attention to detail, but, if it all somehow feels a lot less than the sum of its parts, it may well be because it assumes too much knowledge. Too much exposition can leave a play dramatically clogged, if not actually moribund – one thinks of Plague Over England, the 2008 play about the life of Sir John Gielgud – but too little can leave it feeling anchorless and drifting.

Granville-Barker says at one point that he wonders, all too often in his life, when things are going to be over. I have to say I did start to feel the same way watching this earnest, if rather dull, play.